in so doing, it's destroying all of your ability to mount a defense against any other germ that might come along or any cancer cell that might come along. but that's not all. because h.i.v. is a retro virus, it can also insert its genetic material into selected t4 cells. alexandra levine: and as long as that t4 cell lives, the virus is living also inside of it. we used to think that if we can just keep the virus hidden in the dna there, then eventually those t4 cells will die out and we might be able to cure this. but it turns out that those long-lived "latently infected" t4 cells in which the virus is there, hidden in the dna, they may live 20 or 30 years, and therefore, the ability to really cure this infection may not be possible. ronald mitsuyasu: so it's a very insidious virus that attacks human immune cells, integrates within the cell itself, and then replicates within those cells and then goes on to attack additional immune cells. and the terrifying thing about h.i.v. is that... the patient really does not have an immune response to the virus, and the virus kind of makes sure t